journal article·2016-04

Surface roughening of an aluminum 6016 alloy during bending and hemming

Mathias Liewald, Severin Hönle, Manfred Sindel

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Abstract

Hang-on parts of modern passenger cars such as doors and hoods are mainly manufactured by a two-step hemming process during assembly, whereby the edge of the already deep-drawn, blanked and flanged outer panel is further bent to a hem. This hem ties together outer and inner panel of hang-on part. Owing to the bending processes during hemming, large amounts of strain occur on the outer side of the hemming rope, causing local roughening of the formed sheet surface, which may become critical in terms of the quality of the coated component. In this study, the surface roughening during bending and hemming of a typical aluminum sheet material for hang-on parts is examined. In a first step, the roughening process is determined as a function of the bending angle and plastic strain during bending and hemming. Then hemming was further investigated to describe surface roughening as a function of the flanging radius and pre-strain level. The results of the plate bending test and hemming test at identical bending angles and plastic strain levels showed different levels of surface roughening, caused by the non-congruent size and local position of the forming zone in both bending methods.
Source: openaire · Quality: candidate unverified · Source record ↗

Research context

OpenAlex topics: Metal Forming Simulation Techniques · Advanced Surface Polishing Techniques · Surface Treatment and Residual Stress

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References (33)

Show source-provided references
1. Koch U, Gusinde A, Huppert-Schemme G, Hirsch J, Hornbogen E (1997) Karosseriebänder aus AlMgSi-Legierungen - Einfluß der Lösungsglühung auf die mechanischen Eigenschaften bei der großtechnischen Fertigung. Werkstoffwoche ‘96 - Werkstoffe für die Verkehrstechnik
2. Mattei L, Daniel D, Guiglionda G, Klöcker H, Driver J (2013) Strain localization and damage mechanisms during bending of AA6016 sheet. Mater Sci Eng A 559:812–821. doi: 10.1016/j.msea.2012.09.02810.1016/j.msea.2012.09.028 ↗
3. Lahaye C, Bottema J, De Smet P, Heyvaert S (2000) Aluminium alloy selection for closures with respect to functional demands. SAE Tech Pap. doi: 10.4271/2000-01-2696
4. Daniel D, Shahani R, Baldo R, Hoffmann J (2000) Development of 6xxx alloy aluminum sheet for autobody outer panels: bake hardening, formability and trimming performance. SAE Tech Pap. doi: 10.4271/1999-01-3195
5. Lahaye C, Bottema J, De Smet P, Jonason P et al (1999) Improved AA5182 aluminium alloy as a preferred choice for critical forming operations. SAE Tech Pap. doi: 10.4271/1999-01-3173
6. Sachtleber M, Raabe D, Weiland H (2004) Surface roughening and color changes of coated aluminum sheets during plastic straining. J Mater Process Technol 148:68–76. doi: 10.1016/j.jmatprotec.2004.01.04110.1016/j.jmatprotec.2004.01.041 ↗
7. Hou Y, Yu Z, Zhang W, Jiang H, Lin Z (2009) Surface topography evolvement of galvanized steels in sheet metal forming. Trans Nonferrous Metals Soc China 19:305–310. doi: 10.1016/S1003-6326(08)60269-110.1016/S1003-6326(08)60269-1 ↗
8. Mahmudi R, Mehdizadeh M (1999) Surface roughening during uniaxial and equi-biaxial stretching of 70–30 brass sheets. J Mater Process Technol 80–81:707–712. doi: 10.1016/S0924-0136(98)00099-5
9. Raabe D, Sachtleber M, Weiland H, Scheele G, Zhao Z (2003) Grain-scale micromechanics of polycrystal surfaces during plastic straining. Acta Mater 51:1539–1560. doi: 10.1016/S1359-6454(02)00557-810.1016/S1359-6454(02)00557-8 ↗
10. Stoudt MR, Hubbard JB, Leigh SD (2011) On the relationship between deformation-induced surface roughness and plastic strain in AA5052—is it really linear? Metall Mater Trans A 42:2668–2679. doi: 10.1007/s11661-011-0694-z10.1007/s11661-011-0694-z ↗
11. Lucachick G, Sanchez L (2013) Surface topography changes in aluminum alloy sheet during large plastic straining under cyclic pure bending. J Mater Process Technol 213:300–307. doi: 10.1016/j.jmatprotec.2012.09.01110.1016/j.jmatprotec.2012.09.011 ↗
12. Ogórek A, Stachowicz F (2005) Determination of forming limits of thin aluminium sheets. Scientific bulletin series C: fascicle mechanics, tribology, machine manufacturing technology
13. Roters F, Raabe D, Weiland H (2006) Roughening of coated aluminium sheets during plastic straining. Mater Sci Forum 519–521:711–716. doi: 10.4028/www.scientific.net/MSF. 519-521.71110.4028/www.scientific.net/MSF.519-521.711 ↗
14. Becker R (1998) Effects of strain localization on surface roughening during sheet forming. Acta Mater 46:1385–1401. doi: 10.1016/S1359-6454(97)00182-110.1016/S1359-6454(97)00182-1 ↗
15. Wilson DV, Roberts WT, Rodrigues PMB (1981) Effects of grain anisotropy on limit strains in biaxial stretching: part ii. Sheets of cubic metals and alloys with well-developed preferred orientations. Metall Mater Trans A 12:1603–161110.1007/BF02643566 ↗
16. Mizuno T, Mulki H (1996) Changes in surface texture of zinc-coated steel sheets under plastic deformation. Wear 198:176–184. doi: 10.1016/0043-1648(96)06963-310.1016/0043-1648(96)06963-3 ↗
17. Scheele G (2004) Untersuchung des Aufrauungsverhaltens von Reinaluminium bei Walz- und Zugverformung. Dissertation, Aachen
18. Stoudt MR, Hubbard JB, Iadicola MA, Banovic SW (2008) A study of the fundamental relationships between deformation-induced surface roughness and strain localization in AA5754. Metall Mater Trans 40:1611–1622. doi: 10.1007/s11661-009-9881-610.1007/s11661-009-9881-6 ↗
19. Dautzenberg J, Kals J (1985) Surface roughness caused by metal forming. Ann CIRP-Manuf Technol 34:477–479. doi: 10.1016/S0007-8506(07)61815-010.1016/S0007-8506(07)61815-0 ↗
20. Sarkar J, Kutty TRG, Wilkinson DS, Embury JD, Lloyd DJ (2004) Tensile properties and bendability of T4 treated AA6111 aluminum alloys. Mater Sci Eng A 369:258–266. doi: 10.1016/j.msea.2003.11.02210.1016/j.msea.2003.11.022 ↗
21. Radhakrishnan V (2003) Effect of stylus radius on the roughness values measured with tracing stylus instruments. Wear 16:325–335. doi: 10.1016/0043-1648(70)90099-210.1016/0043-1648(70)90099-2 ↗
22. Debuire F, Zwilling V (2002) Experimental and numerical approaches of hemming: application on steel and aluminum 6016. SAE Tech Pap. doi: 10.4271/2002-01-2084
23. Liewald M, Wagner S (2012) Current Research Work into Sheet Metal Forming at the Institute for Metal Forming Technology (IFU) at the University of Stuttgart. In: Liewald M (ed) International Conference New Developments in Sheet Metal Forming, Conference Proceeding, MAT INFO Werkstoff-Informationsgesellschaft mbH, Frankfurt
24. Hönle S, Liewald M (2013) Prozesssichere Gestaltung von Maschinenfalzprozessen unter Berücksichtigung der Werkstoffbeanspruchung von Karosseriekomponenten aus Blech. In: Brosius A (ed) Sächsische Fachtagung Umformtechnik SFU, Conference Proceeding, Dresden
25. Le Maout N, Thullier S, Manach PY (2010) Classical and roll-hemming process of Pre-strained metallic sheets. Exp Mech 50:1087–1097. doi: 10.1007/s11340-009-9297-710.1007/s11340-009-9297-7 ↗
26. Le Maout N, Thullier S, Manach PY (2009) Aluminum alloy damage evolution for different strain paths—application to hemming process. Eng Fract Mech 76:1202–1214. doi: 10.1016/j.engfracmech.2009.01.01810.1016/j.engfracmech.2009.01.018 ↗
27. DIN EN ISO 6892–1 (2014) Metallic materials - Tensile testing - Part 1: Method of test at room temperature
28. DIN EN ISO 4287 (2010) Geometrical Product Specifications (GPS) - Surface texture: Profile method - Terms, definitions and surface texture parameters
29. DIN EN ISO 7438 (2012) Metallic materials - Bend test
30. Liewald M, Hönle S, Sindel M (2013) Untersuchung des Kraft- und Energiebedarfs beim Falzen von Aluminiumblechwerkstoffen. UTFscience 4/2013
31. Denninger R (2014) Beitrag zur Prozessabsicherung beim Einsatz von Aluminiumblechwerkstoffen für Fahrzeugkarosserien. Dissertation, Stuttgart
32. Hönle S, Liewald M (2014) Experimental investigation of energy savings during table-top hemming of aluminum alloys. Key Eng Mater 611–612:947–954. doi: 10.4028/www.scientific.net/KEM. 611-612.94710.4028/www.scientific.net/KEM.611-612.947 ↗
33. Mishra A, Thuillier S (2014) Investigation of the rupture in tension and bending of DP980 steel sheet. Int J Mech Sci 84:171–181. doi: 10.1016/j.ijmecsci.2014.04.02310.1016/j.ijmecsci.2014.04.023 ↗